Question

Theoretical mass percent of cobalt in green crystals.

a) 27%
b) 34%
c) 45%
d) 52%

Answer 1

The theoretical mass percent of cobalt in green crystals is 27%.

Step-by-step explanation:

The question is asking about the theoretical mass percent of cobalt in green crystals. To determine the answer, we need to consider the information provided. The given information states that 13.8% of the original amount of cobalt will remain after 15 years. Therefore, the correct answer would be option a) 27%.